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The causality between the rapid rotation of a sunspot and an X3.4 flare

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Chinese Journal of Astronomy and Astrophysics 2009年第5期9卷 596-602页

作者： Xiao-li yan Zhong-quan qu cheng-lin Xu Zhi-Ke Xue De-Fang Kong National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming 650011 China Graduate school of Chinese Academy of sciences Beijing 100049 China Yunnan Normal university Kunming 650092 China Jiaxing university Jiaxing 314001 China

Using multi-wavelength data of Hinode, the rapid rotation of a sunspot in active region NOAA 10930 is studied in detail. We found extraordinary counterclockwise rotation of the sunspot with positive polarity before an X3.4 flare. From a series of vector magnetograms, it is found that magnetic force lines are highly sheared along the neutral line accompanying the sunspot rotation. Furthermore, it is also found that sheared loops and an inverse S-shaped magnetic loop in the corona formed gradually after the sunspot rotation. The X3.4 flare can be reasonably regarded as a result of this movement. A detailed analysis provides evidence that sunspot rotation leads to magnetic field lines twisting in the photosphere. The twist is then transported into the corona and triggers flares.

关键词： Sun sunspots - Sun flares - Sun magnetic fields

泛素蛋白酶体系统在变应性鼻炎中作用的研究进展

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生理科学进展 2024年第4期55卷 320-327页

作者：秦竹李岩黑龙江中医药大学研究生院哈尔滨150040 黑龙江中医药大学附属第一医院耳鼻喉科哈尔滨150040

变应性鼻炎的继发性损伤如炎症、氧化应激和线粒体功能障碍,被认为是疾病进展的关键因素。尽管变应性鼻炎有许多治疗方法,例如药物治疗、手术治疗等,但结果并非很理想且副作用多。制定新颖有效的策略来改善患者预后至关重要。泛素蛋白... 详细信息

变应性鼻炎的继发性损伤如炎症、氧化应激和线粒体功能障碍,被认为是疾病进展的关键因素。尽管变应性鼻炎有许多治疗方法,例如药物治疗、手术治疗等,但结果并非很理想且副作用多。制定新颖有效的策略来改善患者预后至关重要。泛素蛋白酶体系统(ubiquitin-proteasome system,UPS)是细胞中各种功能性调节蛋白的加工和代谢的枢纽。它对维持细胞稳态至关重要。随着近年来UPS研究的推进,人们发现UPS在人体的各种生理和病理过程中具有重要的作用。预计UPS将通过多个靶点和途径在变应性鼻炎的发生和发展中发挥作用。本文从与变应性鼻炎相关的信号通路角度探讨了UPS参与疾病的研究进展,以期为进一步研究UPS和变应性鼻炎治疗提供理论依据。

关键词：泛素蛋白酶体系统变应性鼻炎线粒体功能障碍氧化应激

基于CNN与LSTM复合深度模型的恒星光谱分类算法

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光谱学与光谱分析 2024年第6期44卷 1668-1675页

作者：李浩赵青崔辰州樊东卫张成奎史艳翠王嫄天津科技大学人工智能学院天津300457 中国科学院国家天文台北京100012

恒星光谱分类是天文学领域中非常重要的研究方向。随着科技的迅猛发展,大型巡天望远镜采集的恒星光谱数据已经达到了TB或甚至PB级别,传统的分类方法已经无法满足如此庞大数据量的处理需求。正确分类光谱对于研究恒星的物理性质以及演化... 详细信息

恒星光谱分类是天文学领域中非常重要的研究方向。随着科技的迅猛发展,大型巡天望远镜采集的恒星光谱数据已经达到了TB或甚至PB级别,传统的分类方法已经无法满足如此庞大数据量的处理需求。正确分类光谱对于研究恒星的物理性质以及演化过程具有重要意义。CNN通过卷积运算学习数据的局部特征,去除冗余信息,并通过最大池化运算对特征进行压缩。然而,由于原始CNN模型的全连接层缺乏长距离依赖挖掘的功能,如果加入LSTM网络,通过其独特的三个“门”的远距离依赖挖掘能力可提取的重要特征,并检测特征中的微小差异,恰好可以解决这个问题。因此,提出了一种基于CNN和LSTM复合的深度模型,用于对LAMOST DR8中的恒星光谱进行分类。这种模型能够更好地学习恒星光谱的特征,为恒星演化研究提供了重要的帮助。为了提高模型的收敛速度,使用了常见的Z-Score标准化方法对数据进行处理。提出的模型在F、G、K三分类实验中取得了94.56%的分类准确率。同时,与前人使用过的RBM、PILDNN、PILDNN、DBN、Inception v3、1D-SSCNN、LSTM方法进行对比,结果表明该方法具有更高的分类准确率。在十分类实验中,该方法取得了97.35%的准确率,并且相比于仅使用LSTM、1D-SSCNN方法的实验结果,该方法的结果更好,且训练时间减少了近十倍。使用F1-score对每类恒星光谱分类准确度进行说明,在三分类和十分类实验中,每类的F1值都在0.9以上。与前人在文献中的实验结果进行对比,该模型的结果更好。通过混淆矩阵的结果,可以得出该模型在光谱种类越多的实验中准确率越高,甚至可以达到100%。综上所述,所提出的基于CNN和LSTM相结合的模型可以有效地对大规模恒星光谱数据进行分类,并取得了优异的分类效果。

关键词： LAMOST 恒星光谱分类卷积神经网络长短期记忆网络 Z-Score标准化

Predictive H∞ Control for Uncertain Continuous Time-delay Systems

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Predictive H∞ Control for Uncertain Continuous Time-delay S...

2.11 Chinese Control and Decision Conference（CCDC）

作者： Ke-Yong Shao is with the school of Electrical and Information Engineering,Northeastern Petroleum university,Daqing,heilongjiang,163318,china .Wen-cheng li is with the school of Electrical and Information Engineering,Northeastern Petroleum university,Daqing,heilongjiang china .Ying-Ying li is with the school of Electrical and Information Engineering,Northeastern Petroleum university,Daqing,heilongjiang china .Fei li is with the school of Electrical and Information Engineering,Northeastern Petroleum university,Daqing,heilongjiang,163318,china .Hong-yan Zhang is with the school of Electrical and Information Engineering,Northeastern Petroleum university,Daqing,heilongjiang china

In this paper,the problem of robust stability and robust H∞ state observer controller design is researched for a kind of time-delay linear Continuous systems with *** constructing a suitable Lyapunov function,asymptotically stable conditions of systems and a design scheme of the state feedback controllers based on linear matrix inequality approach are proposed without directly measuring the system *** controllers which meet corresponding design demands is obtained by solving the corresponding linear matrix *** results show that this approach is able to make the system asymptotically stable for allowable uncertainties and time-delay,as well as satisfy a certain H∞ property index,and it has the good ability of restraining disturbances.

关键词： Time-Delay Systems Observer Controller Stability H∞ Control

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电裂解芯片及其在细菌核酸分析中的应用

分析测试学报 2024年第3期43卷 373-381页

作者：程洁蔡霜霜王其友陈缵光童艳丽中山大学药学院广东广州510006 南方医科大学附属第三医院广东广州510500 广东省第二人民医院广东广州510310

近年来,由于各种细菌引起的疾病不断爆发,细菌核酸检测已成为常用的实验室诊断方法。细菌核酸提取是细菌分类和鉴定的关键步骤,也是医学诊断、药物筛选的重要技术之一。目前的细菌核酸提取以化学裂解方法为主,其存在明显的缺点,如样品... 详细信息

近年来,由于各种细菌引起的疾病不断爆发,细菌核酸检测已成为常用的实验室诊断方法。细菌核酸提取是细菌分类和鉴定的关键步骤,也是医学诊断、药物筛选的重要技术之一。目前的细菌核酸提取以化学裂解方法为主,其存在明显的缺点,如样品量大、化学试剂污染等。因此,研究快速、简单、无化学污染的检测装置具有重要意义。该研究设计了一种微流控芯片在直流电场下裂解各种细菌并提取核酸。研究了电场强度、电极间距、裂解时间、氧化铟锡电极方阻及电极宽度对核酸提取的影响。结果表明,在3.0 kV/mm的电场强度下,该芯片可在3 s内裂解大肠杆菌、金黄色葡萄球菌、表皮葡萄球菌、枯草芽孢杆菌、肺炎克雷伯氏菌、鼠伤寒沙门氏菌和铜绿假单胞菌等多种细菌,并释放出核酸。提取的核酸无需纯化,可直接用于PCR检测。该芯片与实时荧光定量PCR联用检测细菌DNA的线性范围为10-18~10^(-10)mol/L,检出限低至4.2.10^(-18)mol/L。不同类型的细菌需根据其性质适当调整最佳裂解条件。该研究为病原体分析和细菌感染的医学诊断提供了一种简单、快速、高效且无化学试剂污染的核酸提取方法。

关键词：微流控芯片电裂解核酸提取直流电场多种细菌

Scutellarin protects oxygen/glucose-deprived astrocytes and reduces focal cerebral ischemic injury

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Neural Regeneration Research 2018年第8期13卷 1396-1407页

作者： Jing-Bo Sun yan li Ye-feng Cai yan Huang Shu liu Patrick KK Yeung Min-Zhen Deng Guang-Shun Sun Prince LM Zilundu Qian-Sheng Hu Rui-xin An li-Hua Zhou li-xin Wang Xiao cheng Department of Neurology Guangdong Provincial Hospital of Traditional Chinese Medicine Guangzhou Guangdong Province China Department of Second Institute of Clinical Medicine Guangzhou University of Traditional Chinese Medicine Guangzhou Guangdong Province China Guangdong Provincial Academy of Chinese Medical sciences Guangzhou Guangdong Province China Guangdong Provincial Chinese Emergency Key Laboratory Guangzhou Guangdong Province China Department of Anatomy An Hui Medical University Hefei Anhui Province China Department of Biomedical sciences The University of Hong Kong Hong Kong Special Administrative Region China Department of Preventive Medicine School of Public Health Zhong Shan School of Medicine Sun Yat-Sen University Guangzhou Guangdong Province China Guangzhou Department of Anatomy Zhong Shan School of Medicine Sun Yat-Sen University Guangzhou Guangdong Province China

Scutellarin, a bioactive flavone isolated from Scutellaria baicalensis, has anti-inflammatory, anti-neurotoxic, anti-apoptotic and anti-oxida- tive effects and has been used to treat cardiovascular and cerebrovascular diseases in china. However, the mechanisms by which scutellarin mediates neuroprotection in cerebral ischemia remain unclear. The interaction between scutellarin and nicotinamide adenine dinucleotide phosphate oxidase 2 （NOX2） was assessed by molecular docking study, which showed that scutellarin selectively binds to NOX2 with high affinity. Cultures of primary astrocytes isolated from the cerebral cortex of neonatal Sprague-Dawley rats were pretreated with 2, 10 or 50 μM scutellarin for 30 minutes. The astrocytes were then subjected to oxygen/glucose deprivation by incubation for 2 hours in glucose-free Dulbecco＇s modified Eagle＇s medium in a 95% N2/5% CO2 incubator, followed by simulated reperfusion for 22 hours. Cell viability was assessed by cell counting kit-8 assay. Expression levels of NOX2, connexin 43 and caspase-3 were assessed by western blot assay. Reactive oxygen species were measured spectrophotometrically. Pretreatment with 10 or 50 μM scutellarin substantially increased viability, reduced the expression of NOX2 and caspase-3, increased the expression of connexin 43, and diminished the levels of reactive oxygen, species in astrocytes subjected to ischemia-＇reperfusion. We also assessed the effects of scutellarin in vivo in the rat transient middle cerebral artery occlusion model of cerebral ischemia-reperfusion injury. Rats were given intraperitoneal injection of 100 mg/kg scutellarin 2 hours before surgery. The Bederson scale was used to assess neurological deficit, and 2,3,5-triphenyltetrazolium chloride staining was used to measure infarct size. Western blot assay was used to assess expression of NOX2 and connexin 43 in brain tissue. Enzyme-linked immunosorbent assay was used to detect 8-hydroxydeoxyguanosine （8-OHdG）, 4-hydroxy-2-no

关键词： nerve regeneration scutellarin cerebral ischemic injury oxygen glucose deprivation/reoxygenation nicotinamide adenine dinucleotide phosphate oxidase 2 reactive oxygen species connexin 43 neural regeneration

Effi cacy and safety of low-dose corticosteroids for acute respiratory distress syndrome:A systematic review and meta-analysis

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World Journal of Emergency Medicine 2021年第3期12卷 207-213页

作者： Yu-qing Cui Xian-fei Ding Huo-yan liang Dong Wang Xiao-juan Zhang li-feng li quan-cheng Kan Le-xin Wang Tong-wen Sun General ICU the First Affi liated Hospital of Zhengzhou UniversityHenan Key Laboratory of Critical Care MedicineZhengzhou Key Laboratory of SepsisHenan Engineering Research Center for Critical Care MedicineZhengzhou 450052China Biotherapy Center the First Affi liated Hospital of Zhengzhou UniversityZhengzhou 450052China Department of Pharmacy the First Affi liated Hospital of Zhengzhou UniversityZhengzhou 450052China school of Biomedical sciences Charles Sturt UniversityWagga Wagga 2650Australia

BACKGROUND:There are confl icting results regarding whether corticosteroids have better effi cacy than placebo in acute respiratory distress syndrome(ARDS)***,we aim to further evaluate the effi cacy and safety of corticosteroids in adult ARDS ***:The databases,including Medline,EMBASE,and Cochrane Central Register of Controlled Trials(CENTRAL)in the Cochrane library,were searched from their inception to May 2,*** controlled trials(RCTs)and observational cohort studies were selected to assess the use of corticosteroids in adult ARDS *** quality of the results was judged by the Grading of Recommendations Assessment,Development,and Evaluation(GRADE)*** inverse-variance method with random or fixed effects modeling was used to compute pooled odds ratio(OR),standardized mean diff erence(SMD),and their 95%confi dence interval(CI).RESULTS:Eight eligible RCTs and six cohort studies were *** use of corticosteroids was associated with reduced mortality(OR 0.57,95%CI 0.43-0.76,I2=35.1%,P=0.148)in ARDS patients,and the result was confirmed in the included cohort studies(OR 0.51,95%CI 0.27-0.95,I2=66.7%,P=0.010).The subgroup analysis stratified by the initiation time and duration of corticosteroid use showed that early ARDS and prolonged corticosteroid use had signifi cant survival benefits in the *** low-dose corticosteroid use was also associated with significantly more ventilator-free days and a reduced rate of new infections in ARDS ***:The low-dose corticosteroid therapy may be safe and reduce mortality,especially in patients with prolonged treatment and early ARDS.

关键词： Low-dose Corticosteroid Acute respiratory distress syndrome Mortality Systematic review Meta-analysis

数字经济对城乡“环境-经济”协同发展的影响研究

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杭州电子科技大学学报（社会科学版） 2024年第4期20卷 11-25页

作者：程莉严月岑杨瑾重庆工商大学成渝地区双城经济圈建设研究院重庆400067 重庆工商大学经济学院重庆400067

文章基于2.13—2020年中国省级面板数据,在采用熵权法和耦合协调度模型测度数字经济与“环境-经济”协同发展水平的基础上,运用面板固定效应模型、中介效应模型和门槛效应模型,实证检验数字经济影响“环境-经济”协同发展的效应及作用... 详细信息

文章基于2.13—2020年中国省级面板数据,在采用熵权法和耦合协调度模型测度数字经济与“环境-经济”协同发展水平的基础上,运用面板固定效应模型、中介效应模型和门槛效应模型,实证检验数字经济影响“环境-经济”协同发展的效应及作用机制。研究发现:(1)数字经济显著促进城乡“环境-经济”协同发展。城市维度上呈现“倒U型”特征,且中西部、东北部较东部更显著;乡村维度上呈现“正U型”特征,且东部和东北显著、中西部不显著。(2)城市维度上产业结构高级化、技术创新是数字经济影响“环境-经济”协调发展的重要机制,其中产业结构高级化呈现门槛特征;乡村维度上产业结构高级化、技术创新和监督约束均是数字经济影响“环境-经济”协调发展的重要机制,但不存在门槛特征。因此,因地制宜,实施与本地比较优势相匹配的数字经济发展策略,继续推动产业结构变迁、技术创新,强化监督约束,有机统一“数字乡村”建设和“智慧城市”建设,以城乡联动融合发挥数字经济在促进“环境-经济”协同发展的引导效应。

关键词：数字经济城乡“环境-经济”协同发展熵权法耦合协调度模型中介效应

Hemin-mediated Hemolysis in Erythrocytes:Effects of Ascorbic Acid and Glutathione

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Acta Biochimica et Biophysica Sinica 2006年第1期38卷 63-69页

作者： Shu-De li~(1,2),yan-Dan SU~3,Ming li~1,and cheng-Gang ZOU~(1*) ~1 school of life sciences,Yunnan university,Kunming 650091,china ~2 Department of Biochemistry and~3 Department of Clinical Chemistry,Kunming Medical College.Kunming 650031,china school of life sciences Yunnan University Kunming 650091 China

In the present work,we investigated the effect of ascorbic acid and glutathione on hemolysisinduced by hemin in *** acid not only enhanced hemolysis,but also induced formationof thiobarbituric acid-reactive substances in the presence of *** has been shown that glutathioneinhibits hemin-induced hemolysis by mediating hemin *** depleted of glutathionebecame very sensitive to oxidative stress induced by hemin and ascorbic acid.H2O2was involved in hemin-mediated hemolysis in the presence of ascorbic ***,a combination of glutathione and ascorbicacid was more effective in inhibiting hemolysis induced by hemin than glutathione *** andintracellular ascorbic acid exhibited a similar effect on hemin-induced hemolysis or inhibition of hemin-induced hemolysis by *** current study indicates that ascorbic acid might function as anantioxidant or prooxidant in hemin-mediated hemolysis,depending on whether glutathione is available.

关键词： erythrocyte ascorbic acid hemin glutathione H2O2